When defaulting CET run-time support to auto, check if -fcf-protection
works.  Even if the stage1 GCC doesn't support -fcf-protection, since
the final GCC does, CET run-time support will be enabled by default if
binutils support CET.

config/

	PR bootstrap/95147
	* cet.m4 (GCC_CET_FLAGS): Also check if -fcf-protection works
	when defaulting to auto.

libatomic/

	PR bootstrap/95147
	* configure: Regenerated.

libbacktrace/

	PR bootstrap/95147
	* configure: Regenerated.

libgcc/

	PR bootstrap/95147
	* configure: Regenerated.

libgfortran/

	PR bootstrap/95147
	* configure: Regenerated.

libgomp/

	PR bootstrap/95147
	* configure: Regenerated.

libitm/

	PR bootstrap/95147
	* configure: Regenerated.

libobjc/

	PR bootstrap/95147
	* configure: Regenerated.

libphobos/

	PR bootstrap/95147
	* configure: Regenerated.

libquadmath/

	PR bootstrap/95147
	* configure: Regenerated.

libsanitizer/

	PR bootstrap/95147
	* configure: Regenerated.

libssp/

	PR bootstrap/95147
	* configure: Regenerated.

libstdc++-v3/

	PR bootstrap/95147
	* configure: Regenerated.

libvtv/

	PR bootstrap/95147
	* configure: Regenerated.

zlib/

	PR bootstrap/95147
	* configure: Regenerated.